From download page:
Garuda Linux KDE lite is made for users who do not want extra software and functionalities and complain about bloat. It contains only the bare minimum of packages needed to get started.
(You are on your own, we do not provide any support for KDE lite editions!)
If you read through the forum posts from the last few days you will see many people have needed to reinstall Grub due to a bug that came down in a recent update. If you have not done so yet, that will be worth a shot.
Please post the output of garuda-inxi on all help requests.
That's the issue, you can not use the command line at all! It reports the same error you are basically rendered useless! You write an existing command, it reports you zstd buffer, you write a non existing command it tells you that's an invalid command.